zfsonlinux/zfs — pull request #553 by etienne-dechamps-o (2012-02-03 13:02:05+00:00)
Title: Add support for hole punching operations on files and volumes

These patches add support for the following operations:

- inode operation `truncate_range` on regular files
- file operation `ftruncate(FALLOC_FL_PUNCH_HOLE)` on regular files
- `REQ_DISCARD` on volumes

These operations are related to hole punching (thin provisioning) support. Closes #334.

Note: #384 was the original pull request for this, but I made a new one since I seriously messed up the branch by doing unwanted merges. I'll try to be more careful this time.